Numerous surveys and studies have demonstrated a difference in all-cause and cause-specific morbidity and mortality by age, race/ethnicity, and gender, however the underlying reasons for these disparities are not well understood [1-3]. Some disparities in morbidity and mortality may be explored by observing and monitoring normal physiologic changes or differences in aging and gender. Other factors may be complex interactions of social and cultural constructs. Attributes that describe an individual's place in a socioeconomic structure are examples of these constructs. Morbidity and mortality measures as well as age, race/ethnicity and gender have been demonstrated to differ by various socioeconomic attributes [6-12]. Several problems have confronted the epidemiologic investigation of the contribution made by socioeconomic attributes to disparities in morbidity and mortality measures [13]. First, there is no consensus as to which attribute is to be used to represent so called socioeconomic status. Traditionally, the attributes that have been used include income, employment status, occupation, and years of education either separately or in combination. These measures are typically used to classify an individual according to high, middle and low socioeconomic status at one point in time. Second, many public health surveillance systems do not collect, or have only recently begun collecting, information about socioeconomic attributes. In order for socioeconomic status to be evaluated using public health data sources, additional time and resources are required to collect this information with interviews or questionnaires of registry subjects. Finally, there is growing evidence that neither a single attribute nor a combination of attributes measured for an individual at one point in time fully measure the dynamic construct of socioeconomic status. To address these issues several investigators have used decennial census data to develop indices that describe geographic areas by socioeconomic attributes [13-18]. Census-derived area-based measures have been investigated in England and Wales for many years. In response to problems using social class to explain differences in mortality, several composite measures were developed to address different aspects of public health. Carstairs and Morris [15], Townsend [17], and Jarman [16] developed indices "specifically in the context of health or the health services to seek to explain area variations in health indicators in terms of material deprivation, or for planning health care delivery"